Rubisco gene expression was examined in detail in rice (Oryza sativa L.) leaves at different positions, i.e. expanding, mature, and senescent leaves. Rubisco small subunit (RBCS) synthesis and RBCS mRNA levels were maximal in expanding leaves and gradually became lower in mature and senescent leaves, with declines in those of the large subunit (RBCL) being relatively slower. The amount of synth...

A total of 38 fungal taxa were identified on senescent untreated and autoclaved Castanopsis fissa leaves during a 4-month study period. Seventy-six percent of the fungal genera found in this survey have not previously been recorded from Castanopsis. Frequency and time of occurrence of fungal taxa occurring on untreated senescent leaves were clustered into four groups when analyzed by cluster an...

in this study, nutrition, nutrient return and nutrient retranslocation were compared between two stands of alnus subcordata (n-fixing tree) and taxodium distichum (coniferous deciduous tree), planted on a weak drained soil in north of iran (tashbandan, amol). in each tree stand, n, p, k, ca and mg concentration of fresh and senescent leaves and soil were measured. the concentrations of n and mg...

Chlorophyll breakdown is a hallmark of leaf senescence and a major contributor to the emergence of the fall colors. Strikingly, essential pieces of the puzzle of this biological phenomenon have been solved only within the last two decades. A breakthrough was the identification and structure elucidation of a colorless tetrapyrrolic chlorophyll catabolite, thereafter named Hv-NCC-1. The further c...

Aegiceras corniculatum (L.) Blanco, a mangrove shrub species in the Myrsine family, often grows at the seaward edge of the mangrove zone in China. In the present study, seasonal dynamics of nutrient resorption and phenolics concentration associated with leaf senescence of A. corniculatum were investigated in order to evaluate its possible nutrient conservation strategies in the subtropical Zhan...

The biosynthetic pathway of Chl, probably the most important pigment in the biosphere, has been studied in considerable detail and is mentioned in plant physiology textbooks. Oddly enough, however, the breakdown of Chl is barely mentioned. Yet, as pointed out by Hendry et al. (1987), an estimated one billion tons of Chl are broken down every year, seemingly without leaving a trace. The only enz...

A total of 23 volatile constituents was identified and characterized by GC and GC-MS in the volatile essential oil extracted from intact (juvenile and adult) and fallen (senescent and leaf litter) leaves of lemon-scented eucalyptus (Eucalyptus citriodora Hook.). The leaves differed in their pigment, water and protein content, and C/N ratio. The oils were, in general, monoterpenoid in nature wit...

In this work, the characterization of endoprotease (EP) isoenzymes in peroxisomes is reported for the first time in cell organelles purified from pea leaves (Pisum sativum L.). A comparative analysis of the endo-proteolytic activity in peroxisomes purified from young (15-day-old) and senescent (50-day-old) leaves was carried out. Peroxisomes purified from senescent leaves showed a much higher e...

Chlorophyll breakdown is a visual phenomenon of leaf senescence and fruit ripening. It leads to the formation of colorless chlorophyll catabolites, a group of (chlorophyll-derived bilin-type) linear tetrapyrroles. Here, analysis and structure elucidation of the chlorophyll breakdown products in leaves of banana (Musa acuminata) is reported. In senescent leaves of this monocot all chlorophyll ca...